The present invention relates to an endoscopic inspection tool, particularly to the imaging optics at the distal end of an endoscopic inspection tool, and more particularly to an optic for such a tool which permits high resolution, narrow field of view image, particularly for medical diagnostic applications, such as for inspection of the interior of human biology, and which is optimized for best color fidelity.
In the medical fields, endoscopic inspection tools are generally of a survey nature, i.e., the optical designs of the distal (primary image forming optics) utilize graded index lenses with wide ( less than 50 degree) field of view and long depth ( less than 2 mm) of field of view. These optic designs provide the medical clinician with excellent overall view of the medical problem being diagnosed. These prior designs also suffer from significant optical distortion and image field curvature.
This makes determination of feature size, geometry and relative spatial displacement very problematic. In the case where a close-up, undistorted view of a sample is required, a biopsy is performed and the pathology inspected outside the body. The act of cutting can change the pathology and make accurate diagnosis difficult. Thus, in-sites imaging is the preferred method for rapid and accurate testing.
The optic of the present invention gives the operator a narrow ( less than 20 degrees), undistorted ( less than 5%) image of the sample. The optic of this invention provides a tool for past-survey diagnostic identification and characterization. The optic provides a clear, undistorted view of the pathology and thus enables effective treatment. Such features as preteen endometrial scarring and tissue abnormalities is one area where the optic of this invention would make a significant improvement to currently available instruments.
It is an object of the present invention to provide an imaging optics for an endoscopic inspection tool.
A further object of the invention is to provide an optic having a high resolution and narrow field of view.
A further object of the invention is to provide an optic that is optimized for color correction.
Another object of the invention is to provide an optic at the distal end of an endoscopic tool to enable image coverage over a narrow ( less than 20 degrees) field of view with very low optical distortion ( less than 5%) and high resolution ( less than 100 microns) image, as well as a short working distance ( less than 2 mm).